[PATCH v4 02/37] drm/blend: Get a rotation name from it's bitfield

[Louis Chauvet <louis.chauvet@bootlin.com>]

Having the rotation/reflection name from its value can be useful for
debugging purpose. Extract the rotation property table and implement
drm_get_rotation_name.

Reviewed-by: José Expósito <jose.exposito@redhat.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
---
 drivers/gpu/drm/drm_blend.c | 35 ++++++++++++++++++++++++++---------
 include/drm/drm_blend.h     |  2 ++
 2 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/drm_blend.c b/drivers/gpu/drm/drm_blend.c
index 1f3af27d2418..11d8e13caea3 100644
--- a/drivers/gpu/drm/drm_blend.c
+++ b/drivers/gpu/drm/drm_blend.c
@@ -256,6 +256,31 @@ int drm_plane_create_alpha_property(struct drm_plane *plane)
 }
 EXPORT_SYMBOL(drm_plane_create_alpha_property);
 
+static const struct drm_prop_enum_list rotation_props[] = {
+	{ __builtin_ffs(DRM_MODE_ROTATE_0) - 1,   "rotate-0" },
+	{ __builtin_ffs(DRM_MODE_ROTATE_90) - 1,  "rotate-90" },
+	{ __builtin_ffs(DRM_MODE_ROTATE_180) - 1, "rotate-180" },
+	{ __builtin_ffs(DRM_MODE_ROTATE_270) - 1, "rotate-270" },
+	{ __builtin_ffs(DRM_MODE_REFLECT_X) - 1,  "reflect-x" },
+	{ __builtin_ffs(DRM_MODE_REFLECT_Y) - 1,  "reflect-y" },
+};
+
+/**
+ * drm_get_rotation_name - Return the name of a rotation
+ * @rotation: The rotation mask (DRM_MODE_ROTATE_* | DRM_MODE_REFLECT_*)
+ *
+ * Returns: the name of the rotation type (unknown) if rotation is not
+ * a known rotation/reflection
+ */
+const char *drm_get_rotation_name(unsigned int rotation)
+{
+	if (rotation < ARRAY_SIZE(rotation_props))
+		return rotation_props[rotation].name;
+
+	return "(unknown)";
+}
+EXPORT_SYMBOL(drm_get_rotation_name);
+
 /**
  * drm_plane_create_rotation_property - create a new rotation property
  * @plane: drm plane
@@ -294,14 +319,6 @@ int drm_plane_create_rotation_property(struct drm_plane *plane,
 				       unsigned int rotation,
 				       unsigned int supported_rotations)
 {
-	static const struct drm_prop_enum_list props[] = {
-		{ __builtin_ffs(DRM_MODE_ROTATE_0) - 1,   "rotate-0" },
-		{ __builtin_ffs(DRM_MODE_ROTATE_90) - 1,  "rotate-90" },
-		{ __builtin_ffs(DRM_MODE_ROTATE_180) - 1, "rotate-180" },
-		{ __builtin_ffs(DRM_MODE_ROTATE_270) - 1, "rotate-270" },
-		{ __builtin_ffs(DRM_MODE_REFLECT_X) - 1,  "reflect-x" },
-		{ __builtin_ffs(DRM_MODE_REFLECT_Y) - 1,  "reflect-y" },
-	};
 	struct drm_property *prop;
 
 	WARN_ON((supported_rotations & DRM_MODE_ROTATE_MASK) == 0);
@@ -309,7 +326,7 @@ int drm_plane_create_rotation_property(struct drm_plane *plane,
 	WARN_ON(rotation & ~supported_rotations);
 
 	prop = drm_property_create_bitmask(plane->dev, 0, "rotation",
-					   props, ARRAY_SIZE(props),
+					   rotation_props, ARRAY_SIZE(rotation_props),
 					   supported_rotations);
 	if (!prop)
 		return -ENOMEM;
diff --git a/include/drm/drm_blend.h b/include/drm/drm_blend.h
index c7e888767c81..dc9ea3f61c35 100644
--- a/include/drm/drm_blend.h
+++ b/include/drm/drm_blend.h
@@ -43,6 +43,8 @@ static inline bool drm_rotation_90_or_270(unsigned int rotation)
 
 #define DRM_BLEND_ALPHA_OPAQUE		0xffff
 
+const char *drm_get_rotation_name(unsigned int rotation);
+
 int drm_plane_create_alpha_property(struct drm_plane *plane);
 int drm_plane_create_rotation_property(struct drm_plane *plane,
 				       unsigned int rotation,

-- 
2.54.0